Guidelines for Jubaea seed germination:

1. Collect enough seeds. Fresh seeds become available in September/October.
2. Remove most of the mesocarp fibres to facilitate the cracking procedure. Soaking the seeds in water for one or two days may improve this step. Seeds from previous years have often lost their fibres.
3. Crack and completely remove the Jubea endocarp. The best way to do this is to strike a single blow to make the shell explode. Repeated strokes increase the risk of damage to the seed!
4. Select the supposed viable seeds. A "good" Jubea endosperm displays a chestnut brown skin. The fertile germ is identified as a "flat bright brown tear" stuck on the surface of the endosperm. Exclude endosperms which are cracked, flaccid, dark brown and dehydrated, or which smell bad.
5. Treat as a preventative with a fungicide. Naked endosperms are particularly vulnerable and can rot easily. Place them in a sterile and well drained medium, such as a mix of peat and coarse sand (1:4).
6. Use individual small clay pots rather then a large seed bed. Individual pots prevent rotting seeds from contaminating the other ones. It also prevent roots damage by avoiding early transplantation. Small clay pots will further provide better conditions for the seeding, especially for temperature, humidity and air exchange with the environment.
7. Cover the seeds with just a few millimetres of sand and spray with fungicide as a watering.
8. Place the pots in a saucer and wrap them with a plastic bag to maintain moderate humidity.
9. Put your Jubea Seed in a dark warm room. Temperatures ranging from 20° to 25°C are sufficient, but best results are said to be achieved with 25° to 30°C. Use a bottom heating system if necessary.
10. Open the plastic bag daily to allow fresh air to get in. Spray with fungicide when the humidity seems to reduce. Never allow the medium to be waterlogged or to dry out. Both could mean the death of most seeds. The secret is now for you to now to be patient and your sleeping Jubaea babies will soon wake up!
Caring for Jubaea seedlings:
11. Remove sprouting pots when the seedling is about one centimetre high. It means that the root has already developed and that the seedling is surely strong enough to enter the second step of its life. . . in full light.
12. The general guideline is now to minimize any stress to the seeding. With your small clay pots, you have no hazardous transplantation to do. Do not overpot the seedings (leave them to rest in peace, for as long as a year?)
13. Keep warmth and humidity for the first weeks, for example by placing an inverted plastic bottle on the pot. Warmth will improve root growth.
14. Use fungicide and allow the sand slightly to dry between waterings.
15. Begin a light feeding programme as sand is a poor growing medium (though the endosperm will provide all nutrients at first). Be prepared to loose some seedlings, maybe for the first years. Chilean Wine Palm is not Phoenix nor Chamaerops. . . Nevertheless, good luck with your future Jubaea forest and tell us about your results!
Conclusions:
Cracking the Jubea seeds and completely removing the endocarps appears to be an interesting method to germinate Jubaea. The general method described here is said to be efficient for other Butiinae such as Butia species. Especially for Butia yatay, whose seeds also display a very hard endocarp and a very long germination period. This technique can also be used with Parajubaea.